1. Field of the Invention
This invention relates to a traction device assembly for mounting on a vehicle tire and more particularly to a plurality of traction elements that are transversely positioned in spaced relation on the tire tread with end portions secured for efficient engagement and disengagement to a mounting assembly supported by the wheel rim.
2. Description of the Prior Art
Numerous devices for increasing the vehicle traction on slippery road surfaces, such as snow, ice, mud and the like as alternatives to conventional snow tires are well known in the art. The most commonly known traction device is the tire chain which includes a plurality of cross chains that are positioned transversely on the tire tread. The cross links are interconnected at their end portions by a pair of chains that extend around the periphery of the sidewalls of the tire. The conventional tire chain is difficult to install and in most cases requires that the tire be elevated by jacking the vehicle. Furthermore, when a single link of the tire chain breaks, the broken ends remain engaged to the assembly so that as the tire continues to rotate as the vehicle moves, the free ends of the chain lash the vehicle body and inflict considerable damage thereto. Also, a single broken chain renders the assembly inoperative requiring replacement of the entire tire chain assembly.
U.S. Pat. Nos. 3,856,069 and 3,945,162 disclose modifications to the conventional tire chain in which the cross links are supported on the vehicle tire by strap assemblies positioned inboard and outboard of the tire with the frame and to a backing plate mounted between the wheel and the brake drum with the latter. These modifications to the conventional tire chain are designed to permit the cross links to be tightly held against the tire tread so as to maintain a fixed position on the tread and thereby reduce strain applied to the cross links that contributes to breaking of the chain. A commercially known embodiment of this type of snow tire is manufactured and sold by Detwiler Corp. of Westbury, New York and marketed under the name "SNO-TREADS" in which snow straps are substituted for the cross chains and are secured to the tire at a plurality of points therearound by belts that extend around the tire on the sidewalls. However, as with the devices illustrated in the above mentioned patents, traction devices of this type must be draped over the tire tread with the end portions hooked and the tire assembly tightened and retightened to adjust them after initial use. The cross chains or straps are interconnected so when one chain or strap is broken the entire assembly becomes inoperative.
To overcome the disadvantage of traction elements being interconnected it is known to independently connect each chain or traction device to the tire as illustrated in U.S. Pat. Nos. 1,102,017; 1,599,001; 2,575,263; 2,598,594; 2,729,262; 3,362,450; 3,473,593 and 3,513,897. A principal feature of these patents is supporting the cross chains independently on the tire tread by securing the end portions of the chain to the wheel rim or to circular members that are mounted within the rim and rigidly secured to the wheel. Because each of the cross chains are independently supported on the tire each must be separately installed and the number of cross chains or traction elements that are mounted on the tire is determined by the driving conditions. The primary difficulty encountered is securing the innermost end of the cross chain to the unexposed inside or inboard rim of the wheel or the circular member mounted on the wheel adjacent to the brake drum. The installer is required to reach under the vehicle fender, over the tire and behind the tire and then locate the end portion of the cross chain with the particular point of attachment. This arrangement is considerably inefficient, and the task of locating the end portion within one of a plurality of holes of reduced dimension on the periphery of the mounting assembly, is quite burdensome. Furthermore, if both ends of the cross chains are tightly secured to the mounting assembly on the wheel so as to prevent relative movement of the traction device on the tire tread and the traction device breaks, the severed portions remain secured to the mounting assembly resulting in considerable damage by lashing at the vehicle body.
There is need for traction devices for vehicle tires in which the traction devices are adapted for quick and easy mounting and dismounting and are readily replacable without dismounting the entire traction assembly on the tire so that a damaged traction device may be easily replaced without rendering the entire assembly inoperative.